Wurlitzer 206A
S/N 127281L
Steve Graham
Estimated 1980 – Model 206A pianos were made from 1974-1983 with the last serial number being 133144L. On back of action rail is stamped 80414047 (code interpreted as YYMMDDXXX). Suggests April 14 1980. Serial number ending in L indicates built at Logan Utah plant.
Resources for Steve Graham
Service ManualInitial Plans
- Regulate Keyboard
- Inspect Amp Circuit (complaint – not working)
- Add Vibrato
- Add Aux Out
- Consider removing wiring from large multi-pin jacks on rear (removes shock hazard), potentially install IEC AC jack like a 200/200A
- Consider adding 4×8 speakers in piano lid
Service Log
Regulate Keyboard
- Disassemble piano, remove action rail
- Inspect & clean capstans
- Check if key easing needed. Not necessary
- Regulate piano
- Quicken keyboard action:
- Remove each whip assembly one at a time and lubricate all 3 action centers (wood/felt/pin) with 8 parts naptha/1 part silicone. Reassemble each whip back into the action rail..
- 1 broken whip – install new one (lowest note)
- Remove hammer assemblies one at a time and lubricate action centers, reassemble.
- Lube key posts with Vintage Vibe key post lube
- Reinstall keys,
- Clean key tops
- Set Lost Motion:
- adjust bottom capstan screws (ensuring the jack accurately returns in the hammer butt on slow return of a depressed key)
- Install harp
- Check that hammers hit center of reeds while avoiding braces
- Install damper rails.
- Reassemble piano
- Top 2 keys (B6 & C6) stick when depressed. The front of hammers’ felt rubbed against the harp assembly – would catch and not release. Filed down front of hammer felts just enough to clear harp assembly.
- Check key height
- Adjust damper screws and adjust damper felts so all reeds are equally dampened
- Set each key’s let off with regulating capstan screws (evens out loud/soft notes and evens feel)
- Voicing – adjust each pickup to bottom of reed to increase or decrease harmonics. On a few softer notes, I adjusted the reed very slightly to one side of the pickup to increase its volume relative to the other notes.
Rebuild Amp PCB
Adding Vibrato & Aux Out using Vintage Vibe’s 206A > 200A conversion kit
- Remove piano’s selector switch pot – install new 50k pot w/ 18k resistor across lugs 2 & 3
- Remove R57 12k from reed bar preamp
Change components on amplifier board (203724)
- Remove C22 1mF (used for teacher microphone circuit & adds hiss)
- Install:
- R17 4.7k trim pot 1 & adjust to ~ 2:00
- R13, R14, R15 680k
- R16 10k
- R12, R41 27k
- R18 680ohm
- R21 & R41 27k
- R42 120k
- R43 1.8k
- R44 15k
- R46 120 ohm
- R47 56k
- R48 180 ohm
- Q3 & Q4 142083-2
- Q15 & Q16 (later model versions)
- C10 22mF 25v
- C16, C17, C18 .12uF 100v
- C23 1uF 25v
- C24, C25 39pF 25v
- C26 & R59 4.7uF & 25v in series
- C27 47uF 10v
- LDR photoresistor
- Jumper wire & posts
Install amplifier into piano and test – No Sound
Double-check & reflow solder points on amplifier PCB
Install replacement transistors set (27) from Busted Gear:
- Small signal transistors:
- TR1, TR2, TR15 2N5089 NPN
- TR3, TR4 2N5088 NPN
- TR7, TR8 2N5087 PNP
- TR9, TR10, TR14 MPSA06 NPN
- TR12 MPSA56 PNP
- TR16 MPSA14 NPN
- Output Transistors:
- TR11 TIP36C PNP
- TR13 TIP35C NPN
Install 1/4″ Aux output and potentiometer under piano left side
Install switch to mute internal speakers (when using Aux Output) under the piano in the old control center cluster.
PARTS
VINTAGE VIBE ORDER #22432
Wurlitzer 206 / 200A 1/4″ Jack Plate $8.00
Wurlitzer 200 Series Lid Hardware Kit $10.00
Piano Key Post Lube $12.50
Wurlitzer 206A Vibrato / Aux Output Kit $90.00
Wurlitzer 140, 200 Whip Assembly – 200 $12.00
Subtotal: $132.50
BUSTED GEAR
Qty. 1 Wurlitzer 200A Small-Signal Transistor Kit $ 16.98
Qty. 2 Wurlitzer 200A Output Transistor Kit $ 20.96
Qty. 2 1.5 amp glass fuse with axial leads for Wurlitzer 200A $ 9.00
Qty. 4 Pigtail Adapter Springs for 1/4″ fuses $ 6.00
Subtotal: $52.94
TOTAL PARTS: $185.44